Aluminum nitride (AlN) powder is an excellent filler material for thermally-conductive polymer composites used as heat sink materials in the electronics industry. However, using virgin aluminum nitride powder in polymer composites is not without its problems. Polymer composites exhibit some water permeability, and, because aluminum nitride is sensitive to hydrolysis, some protection of the aluminum nitride powder from hydrolysis is desired. Additionally, when virgin aluminum nitride powder is stored, air-borne moisture attacks the aluminum nitride powder causing the powder to experience an increase in oxygen content and a concomitant weight gain.
It is, therefore, desirable to provide a moisture-resistant aluminum nitride-containing powder and an easy method for its manufacture.